diff --git a/build.gradle.kts b/build.gradle.kts
index 2c1fd190..8b1c5997 100644
--- a/build.gradle.kts
+++ b/build.gradle.kts
@@ -47,7 +47,10 @@ allprojects {
     }
 
     kotlin {
-        compilerOptions.jvmTarget.set(JvmTarget.JVM_1_8)
+        compilerOptions {
+            jvmTarget.set(JvmTarget.JVM_1_8)
+            freeCompilerArgs.add("-Werror")
+        }
     }
 
     tasks {
diff --git a/kotlin-mbedtls-netty/src/jmh/kotlin/benchmark/netty/NettyBenchmark.kt b/kotlin-mbedtls-netty/src/jmh/kotlin/benchmark/netty/NettyBenchmark.kt
index fe46632a..aeb7037a 100644
--- a/kotlin-mbedtls-netty/src/jmh/kotlin/benchmark/netty/NettyBenchmark.kt
+++ b/kotlin-mbedtls-netty/src/jmh/kotlin/benchmark/netty/NettyBenchmark.kt
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2022-2023 kotlin-mbedtls contributors (https://github.com/open-coap/kotlin-mbedtls)
+ * Copyright (c) 2022-2024 kotlin-mbedtls contributors (https://github.com/open-coap/kotlin-mbedtls)
  * SPDX-License-Identifier: Apache-2.0
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -133,7 +133,7 @@ open class NettyBenchmark {
                 "direct" -> PooledByteBufAllocator(true)
                 "unpooled" -> UnpooledByteBufAllocator(false)
                 "heap" -> PooledByteBufAllocator(false)
-                "heap-8kb" -> PooledByteBufAllocator(false, 2, 2, 8192, 1)
+                "heap-8kb" -> PooledByteBufAllocator(false, 2, 2, 8192, 1, 256, 64, false)
                 // Note: max order is set to 2 so that allocated single byte[] is 8kB, with default one it is 4MB and slows down drastically performance
 
                 else -> throw IllegalArgumentException()
diff --git a/kotlin-mbedtls-netty/src/main/kotlin/org/opencoap/ssl/netty/CompletableQueue.kt b/kotlin-mbedtls-netty/src/main/kotlin/org/opencoap/ssl/netty/CompletableQueue.kt
index 47fbd22e..dafa9b86 100644
--- a/kotlin-mbedtls-netty/src/main/kotlin/org/opencoap/ssl/netty/CompletableQueue.kt
+++ b/kotlin-mbedtls-netty/src/main/kotlin/org/opencoap/ssl/netty/CompletableQueue.kt
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2022-2023 kotlin-mbedtls contributors (https://github.com/open-coap/kotlin-mbedtls)
+ * Copyright (c) 2022-2024 kotlin-mbedtls contributors (https://github.com/open-coap/kotlin-mbedtls)
  * SPDX-License-Identifier: Apache-2.0
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -24,7 +24,7 @@ internal class CompletableQueue<T> {
 
     @Synchronized
     fun add(obj: T) {
-        if (!queue.isEmpty() && !queue.first.isDone) {
+        if (!queue.isEmpty() && !queue.first().isDone) {
             queue.removeFirst().complete(obj)
         } else {
             queue.addLast(CompletableFuture.completedFuture(obj))
@@ -33,7 +33,7 @@ internal class CompletableQueue<T> {
 
     @Synchronized
     fun poll(): CompletableFuture<T> {
-        if (!queue.isEmpty() && queue.first.isDone) {
+        if (!queue.isEmpty() && queue.first().isDone) {
             return queue.removeFirst()
         }
         val promise = CompletableFuture<T>()
diff --git a/kotlin-mbedtls/src/main/kotlin/org/opencoap/ssl/transport/DtlsTransmitter.kt b/kotlin-mbedtls/src/main/kotlin/org/opencoap/ssl/transport/DtlsTransmitter.kt
index 4740d6c3..8a48ae5f 100644
--- a/kotlin-mbedtls/src/main/kotlin/org/opencoap/ssl/transport/DtlsTransmitter.kt
+++ b/kotlin-mbedtls/src/main/kotlin/org/opencoap/ssl/transport/DtlsTransmitter.kt
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2022-2023 kotlin-mbedtls contributors (https://github.com/open-coap/kotlin-mbedtls)
+ * Copyright (c) 2022-2024 kotlin-mbedtls contributors (https://github.com/open-coap/kotlin-mbedtls)
  * SPDX-License-Identifier: Apache-2.0
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -162,7 +162,6 @@ class DtlsTransmitter private constructor(
         }
 
         @JvmStatic
-        @JvmOverloads
         fun create(dest: InetSocketAddress, sslSession: SslSession, cnnTransmitter: Transport<ByteBuffer>): DtlsTransmitter {
             return DtlsTransmitter(dest, cnnTransmitter, sslSession, newSingleExecutor())
         }